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The Southern North Sea Basin area, stretching from the UK to the Netherlands, has a rich hydrocarbon exploration and production history. The past, present and expected future hydrocarbon and geothermal exploration trends in this area are discussed for eight key lithostratigraphic intervals, ranging from the Lower Carboniferous to Cenozoic. In the period between 2007 and 2017, a total of 95 new hydrocarbon fields were discovered, particularly in Upper Carboniferous, Rotliegend and Triassic reservoirs. Nineteen geothermal systems were discovered in the Netherlands onshore, mainly targeting aquifers in the Rotliegend and Upper Jurassic/Lower Cretaceous formations. Although the Southern North Sea Basin area is mature in terms of hydrocarbon exploration, it is shown that with existing and new geological insights, additional energy resources are still being proven in new plays such as the basal Upper Rotliegend (Ruby discovery) for natural gas and a new Chalk play for oil. It is predicted that hydrocarbon exploration in the Southern North Sea Basin area will probably experience a slight growth in the coming decade before slowing down, as the energy transition further matures. Geothermal exploration is expected to continue growing in the Netherlands onshore as well as gain more momentum in the UK.

The dominant fault trends in the southern part of Dutch offshore are NW-SE and NE-SW, which formed during the Paleozoic. During post-Carboniferous tectonic phases, only few new faults formed at Rotliegend level, but the pre-existing basement faults were reactivated repeatedly and penetrated into Rotliegend sediments. Under different tectonic regime and stress direction, different trends of basement faults were reactivated from different angles. The high quality of 3D Seismic data allows for an improved fault analysis in Cleaver Bank High, which is located in the central part of Dutch offshore. Five distinct fault trends were recognized at Base Zechstein level, including NW-SE, NNW-SSE, WNW-ESE, NE-SW and N-S. This study determined when the faults were reactivated since the Permian, and found oblique reactivation on pre-existing faults in the study area. This information leads to a better understanding on the structural development. Reactivation of old faults resulted in the formation of new petroleum traps or the destruction of originally exited ones. So the improved understanding of the fault reactivation also helps to decrease the risk of petroleum exploration.

Sedimentary basins are affected by a large number of forcing factors during their evolution and as a result, it is often difficult to isolate the contribution of each individual factor. Many forcing factors are temporally and spatially heterogeneous; they do not affect all parts of the basin in the same way and at the same time. We show that this heterogeneity can be used to identify the contributions of forcing factors by comparing various parts of a basin. This approach is applied to the Pannonian Basin, a back-arc basin located in Central Europe. In the basin, the amounts of crustal extension, tectonic inversion and sediment influx varied in space and time, while the connection with the marine realm fluctuated. In this study we focus on two currently unresolved issues: firstly, we establish by what processes and from what directions the basin was filled in, and secondly, we investigate whether the basin was affected by the Messinian Salinity Crisis. The analysis of seismic and well data in the previously less studied SE part of the basin demonstrate that progradation occurred from the southern and eastern basin margins, complementing the previously described progradation from the northwestern and northern basin margins. Elsewhere in the basin, an unconformity observed in the progradational basin infill is intensely debated to be the result of either the Messinian Salinity Crisis (MSC) or basin inversion. Having the advantage of minor Pliocene–Quaternary amounts of inversion in the studied part of the basin we show that no regional unconformity is present in the studied stratigraphic interval, which implies that the effects of the MSC on the basin were minor. We infer that being aware of the fact that the effects of relative sea/lake-level fluctuations may vary significantly across a basin is critical for understanding the evolution of semi-enclosed basins.